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41.
Chenglong Yu a b Xin Hao a Hongtao Jiang a Lili Wang a a School of Materials Science Engineering Shaanxi University of Science & Technology Xi’an China b Research Laboratory of Hydrothermal Chemistry Faculty of Science Kochi University Kochi Japan 《中国颗粒学报》2011,9(1)
Fe 3 O 4 nano-whiskers were synthesized via ultrasonic-aided reduction of FeCl 2 ·4H 2 O with N 2 H 4 ·H 2 O in concentrated NaOH solution. Phase identification and morphology observation were conducted by X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM). Face scanning energy dispersive spectrum (face scanning EDS) and two-dimensional fast Fourier transform (2DFFT) for element distribution were carried out for confirming compos... 相似文献
42.
通过微弧氧化法在Na3PO4+K2Cr2O7电解液中制备了系列铬掺杂二氧化钛薄膜. X射线和扫描电镜显示薄膜的主要晶相为锐钛矿型二氧化钛,且表面为多孔结构. 在可见光照射下,薄膜对降解亚甲基蓝和分解水有着较好的光催化性能,这主要是由铬的掺杂引起的.由于铬的掺杂,一方面在二氧化钛中形成了Cr3+/Cr4+离子对,另一方面在带隙中形成了氧的空位能级. 前者降低了电子-空穴的复合几率,而后者在二氧化钛的禁带中形成了新的能级. 新能级的形成使得由二氧化钛价带跃迁至氧空位能级所需的光子能量减少. 另外探讨了微弧氧化形成掺杂二氧化钛薄膜的机制. 相似文献
43.
44.
以磷钼酸作为催化剂,芳香醛、胺和三丁基烯丙基锡三组分在水作为溶剂,室温下高产率的得到相应的烯丙基胺。 相似文献
45.
46.
Photochemical degradation of environmentally persistent perfluorooctanoic acid (PFOA) in the presence of Fe(Ⅲ) 总被引:1,自引:0,他引:1
Yuan Wang~ 《中国化学快报》2008,19(3):371-374
Environmentally persistent and bioaccumulative perfluorooctanic acid (PFOA) was difficult to be decomposed under the irradiation of 254 nm UV light. However, in the presence of 80μmol/L Fe(Ⅲ), 80% of PFOA with initial concentration of 48μmol/L (20 mg/L) was effectively degraded and 47.8% of fluorine atoms in PFOA molecule were transformed into inorganic fluoride ion after 4 h reaction. Shorter chain perfluorocarboxylic acids bearing C3-C7 and fluoride ion were detected and identified by LC/MS and IC as the degradation products in the aqueous solution. It was proposed that complexes of PFOA with Fe(Ⅲ) initiated degradation of PFOA irradiated with 254 nm UV light. 相似文献
47.
48.
W18Cr4V 总被引:2,自引:1,他引:1
The frictionand
wear characteristics of the surfa ce compound layer of W18Cr4V steel by combined treatment
of ion nitrocarburizing-ion sulphurizing were investigated. The friction coefficient of
the compound l ayer against GCr15 steel was determined witha block-ring friction tester.
The wear test was carried out with a reciprocating wear tester. The worn surface was
analyzedby scanning electron microscopy(SEM). The experimental results reveale d that the
friction coefficient was lower for treatedW18Cr4V steel against GCr1 5 steel. The wear
resistance of the compound layer was higher because the nitroc arbonide andthe sulphide in
the compound layer were capable of friction-reduct ion and adhesion-inhibition. 相似文献
49.
Xuexi Tie a Junji Cao b a National Center for Atmospheric Research Boulder CO USA b SKLLQG Institute of Earth Environment Chinese Academy of Sciences No. Fenghui South Road High-Tech Zone Xi’an China 《中国颗粒学报》2010,8(1)
PARTICUOLOGY regrets that the above paper was mistakenly classified as a ‘Review’ rather than an ‘Invited paper’ when originally published in volume 7, issue 6, 426–431. 相似文献
50.
LI Hao-Honga CHEN Zhi-Ronga② REN Yong-Gang LI Jun-Qiana b HUANG Chang-Canga ZHAO Bina a 《结构化学》2005,(12)
1 INTRODUCTION terested in the unique effects associated with substituents at 4- and 7-positions of the phenan- The coordination chemistry of 1,l0-phenanthroline throline ring. Thus, when phenyl groups are present, and its derivatives has captured the attention of che- the absorptivities of the CT transitions are increased mists for years. The reports on biological importance[1~4], markedly due to the extension of the dipole moment supramolecular chemistry[5], electronic spectra[6], conne… 相似文献